Suppressive Effects of Welsh Onion Extracts on Mucus Hyper-Production in Human AIrway Cells

We investigated the suppressive effects of Welsh onion (Allium fistulosum L.) on the hyper-production of mucins in NCI-H292 human lung cancer cells. Periodic acid-Schiff staining showed that the 50% (v/v) ethanol extract of Welsh onion suppressed mucus glycoprotein production in cells, whereas the water and ethanol extracts did not. A real-time RTPCR analysis demonstrated that the 50% ethanol extract attenuated the gene expression of MUC2 and MUC5AC, which are major airway mucus components, in NCI-H292 cells stimulated with lipopolysaccharide (LPS). Furthermore, dot blot hybridization revealed that the extract at 100 μg/ml attenuated the hyper-production of the MUC5AC protein in LPS-stimulated NCI-H292 cells.